Another name for color fastness is dye fastness. It refers to the resistance of textile colors to effects such as color change or transfer during processing and use. The fastness grade, i.e., the degree of color fastness of fabric, is evaluated according to the discoloration of a sample and the staining of the undyed lining fabric.
During use, textiles are usually exposed to external factors such as light, washing, ironing, sweat, friction, and chemical agents. Some printed and dyed textiles ar